1. Field of the Invention
Polymerized oils (“heat-bodied oils”), blown oils (“heavy bodied blown oils”), vegetable-based copolymer oils, and vegetable oil/vegetable-based copolymer oil blends were hydrogenated to make a semi-crystalline wax-like material. The hydrogenated products can be used as bio-renewable replacements for micro-crystalline wax and petrolatum raw materials in products that are comprised of such materials.
2. Background Art
Petrolatums and micro-crystalline waxes are components in a large number of products ranging from personal consumer goods to industrial lubricants. Petrolatums and micro-crystalline waxes are derived from petroleum. Thus, the supply of such ubiquitous raw materials is non-renewable. Petrolatums are semisolid mixtures of hydrocarbons, and are neutral, unctuous, odorless, and tasteless. They have applications in the formulation of products such as creams, lotions, hair preparations, cosmetics, candles, ointments, lubricants and coatings. Typical petrolatums have cone penetration of above 100 dmm and less than 275 dmm (ASTM D937). The melting range of petrolatums is about 38° C. to about 60° C. Micro-crystalline wax is a solid mixture of linear, branched and cyclic hydrocarbons derived from petroleum. It is obtained from the heavy lubricating oil fraction derived from crude oil, subsequent to the removal of paraffin wax. Its characteristics resemble those of the natural waxes closely, including its high melting point, high viscosity, flexibility at low temperatures, and high cohesion and adhesion. Micro-crystalline waxes are usually higher in molecular weight, viscosity and melting point than paraffin wax. Typically, micro-crystalline wax melting points range from 54° C. to about 102° C. They have needle penetration of above 3 dmm and less than 100 dmm (ASTM D1321). Viscosities are higher than 5.75 centistokes at 100° C.
Heat polymerized oils (“polymerized oils”), often referred to as heat bodied oils, are prepared from unsaturated oils. Linseed, safflower and soybean oils are commonly used as the starting materials for this process. In addition, fish oils are commonly heat polymerized. Depending on the oil used, the temperature is held between about 288° C. to about 316° C. until a product with a desired viscosity is obtained. Longer reaction times are used to reach a higher viscosity product. The viscosity of polymerized oils can range from P to Z9. During the reaction, the unsaturated triglycerides react to form polymers. As polymerization takes place, new carbon-carbon bonds are formed between triglyceride units.
Polymerized oils have some improved properties for paint, coatings and ink applications in comparison to unsaturated triglycerides. These properties include improved leveling, pigment wetting, and less yellowing. Typical polymerized oils still contain a high amount of unsaturation. The iodine value (“IV”) of heat bodied linseed oils ranges from approximately 115-150. Polymerized oils are reactive, viscous liquids at room temperature.
Blown oils differ from polymerized oils. Blown linseed oil is prepared by bubbling air through the oil while heating to temperatures of about 110° C. During the process, the oil is polymerized and partially oxidized.
Vegetable-based copolymer oils such as maleinized and dicyclopentadiene oils are characterized by a fast drying time and water resistance. Blending such copolymer oils with vegetable oils yields oil blends that also possess characteristic properties and provides more diversity of chemical properties. Other attributed properties can include the unique hardness of a dried coating when such copolymer oils are incorporated into paint or coating formulations.